Methods to investigate the temperature distribution of heated ceramic gas sensors for high-temperature applications

The temperature-dependent properties of sensor films for measuring the concentration of various gas components affect, to a large extent, the sensor characteristics of planar gas sensors. Therefore, it is important to know the temperature distribution of the gas-sensitive films of suchsensors precisely. Using screen-printed thermocouples and a thermal-imagingcamera, two principles for determining the temperature profile of gassensors inside of a protection cap are shown and compared in this study. Thedata agree well, and the results can be used in future to determine theinfluences of varying flow and temperature conditions on the temperatureprofile of a sensor and to reduce such effects by adapting the periphery, e.g.,by designing appropriate protection caps.